Weight loss, no appetite and fatigue: what to know

Reduced appetite can follow an infection such as COVID-19, ongoing stress or burnout, alcohol-related problems, or digestive conditions such as coeliac disease. Fatigue and weight change can also occur with anaemia, chronic kidney disease, or chronic fatigue syndrome. Dehydration may worsen weakness, dizziness, dry mouth, and low energy. These symptoms overlap across many conditions, so they do not identify one cause by themselves.

A clinician may review your timeline, mood, sleep, bowel symptoms, thirst, medicines, alcohol use, and food and fluid intake. Examination and selected tests can help distinguish nutritional, hormonal, inflammatory, infectious, and organ-related causes.

Arrange a medical appointment if the symptoms persist, are worsening, or are affecting daily activities. Record your weight trend, meals, fluids, fever, bowel changes, sleep, and any pain. Take small frequent meals and regular sips of fluid if tolerated; choose nourishing foods rather than relying on supplements without advice. Bring a list of medicines and explain any recent illness, stress, or change in alcohol use.

Seek urgent help for confusion, fainting, severe breathing difficulty, chest pain, severe abdominal pain, blood in vomit or stool, or inability to keep fluids down. Prompt assessment is also needed for marked weakness, very little urine, or rapidly worsening symptoms. Do not wait for a routine appointment if you feel acutely unwell.

Ask which causes need checking first, whether blood or urine tests are appropriate, and how to protect your nutrition and hydration while waiting. Tell the clinician about appetite, sleep, mood, bowel habits, pain, fever, alcohol, and all medicines or supplements.